Spring construction.



MCCLHLLAN NIUINTOSH.

SPRING CONSTRUCTION.

APPLIOA'I'XON nun JAN.10,1912.

Patented July 23, 1912 muamtoz MC/ellq 11 M l" ta 5 ll UNITED STATES PATENT OFFICE.

MOCLELLAN McINTOSH, OF ALLEGAN, MICHIGAN, ASSIGNOR OF TWO-THIRDS TO FRANK A. EWER AND JOHN T. CLONEY, BOTH OF ALLEGAN, MICHIGAN.

SPRING CONSTRUCTION.

Specification of Letters Patent.

Patented July 23, 1912.

Application filed January 10, 1912. Serial No. 670,533.

To all whom it may concern- Be it known that I, MCCLELLAN Mo- Ix'rosn, a citizen of the United States, residin at Allegan, in the county of Allegan and btate of Michigan, have invented cer tain new and useful Improvements in Spring Construction, of which the following is a specification.

My invention relates to improvements in platform spring construction, and its objects are: first, to provide a platform spring with which pressure on any portion of the surface of the platform will depress the entire platform uniformly, and, second, to provide a means whereby the fulcrum points that support the platform may be readily changed to adjust the resisting power of the spring tov varying weights that may be placed upon the platform. I attain these objects by the construction and mechanism illustrated in the accompanying drawing, in which Figure l is a plan of my invention with the platform frame in place. Fig. 2 ,is a

vertical section of the same on the line :0 w-

of Fig. 1, with one form of su porting frame under it, and Fig. 3 is an e evation of the same with a modified form of supporting frame under it.

Similar letters refer to similar parts throughout the several views.

A represents the frame upon which the platform or other supporting elements are secured. In the construction of this spring I make use of a proper number of arms, as B B which are pivoted together by any available form of hinged appliance, as (l. The opposite ends of one pair of these arms are pivotally secured to one cross rail of the frame Aby any suitable pivotal appliance, a, and the free ends of the other pair of arms are arranged to move freely upon the antifriction rollers a, one of which is shown in Fig. 2. These arms may he supported upon any form of frame, as (t or G and are fulcrumcd over rollers, as l) l), or any other available form of fulcrum, and these fulcrums are made adjustable longitudinally of the arms B B by means of a lever F that is fulcrumed at f and has connecting rods E E that are pivotally secured at one end to the lever F and the other ends are bent to pass through the centers of the rollers I) D to form axial bearings for the rollers to revolve over. By this comitruction the rollers may be readily shifted by simply shifting the lever F, as for instance, with the lever in the position of the solid lines in Fig. l the rollers will be drawn well toward the center of the frame or the hinged ends of the arms, but with the lever carried around to the position indicated by its dotted lines the rollers will be carried toward the outer ends of the arms, thus greatly reducing the leverage upon the spring H- and increasing the supporting or sustaining qualities of the spring.

I prefer that the spring H be placed inside of a protecting jacket as indicated in Figs. 2 and 3, and with one end secured to the bottom of the jacket, as at h and the other end secured to the arms B, as at It" so that any weight placed upon the frame A, or any deck that may be placed on said frame, will force the outer ends of the arms I- B downward over the fulcrums D D and the inner ends will be raised accordingly and draw upon the spring ll, and the posi tion of the rollers upon the supporting frame (lr or G will be regulated to meet the weight to be supported by the spring ll, or in other words, if a light weight is to he supported on the frame the fulcrum points are placed near the inner ends of the frame and arms, but as the weight is increased the fulcrum points are gradually removed toward the outer ends of the arms, it being understood that the 'arms B It and the plate. or girts G or G of the supporting frame must be placed in exact alinemcnt so there will be no friction when the fulcrum points D D are being adjusted to meet varying weights on the platform. The dotted lines in Fig. 3 indicate the position of the platform when depressed by any weight. that may be placed upon it. It will be readily understood that with this construction and distribution of fulcrum points a weight placed even upon an extreme corner of the platform, as at A--l at the upper right hand corner of Fig. 1 will musethecntire platform to be depressed uniformly, exactly as it would be if the weightwere placed upon the exact center of the bed or platform.

\Vhat I claim as new and desire to secure by Letters Patent of the United States, l.\?

1. In spring constructiml, a supporting frame having thin plates, a platform hav- .ing arms pivotally secured thereto at one end, and arms slidably connected therewith at the other end, the other ends of said arms being pivotally connected over the center of the frame and in alinement with the plates of the frame, a spring secured in the frame and connected with the connected ends of the arms, and fulcrum members between the frame and the arms.

2. In spring construction, a supporting frame, a platform, two pairs of arms pivotally connected at one end, the opposite ends vof one pair of arms pivotally connected to the platform and the opposite ends of the other pair ,of arms slidably connected with the other end of the platform, fulcrum members adjustably supported between the frame and the arms, a lever pivotally supported centrally of the platform below the arms, and connecting rods connecting said lever with the fulcrum members so that any movement of the lever will change the position of the fulcrum members, and a spring connected with the frame, and with the arms where they are pivotally connected, as shown,

Mb, 1912. McCLELLAN MCINTOSH.

In presence of- T. S. UPDYKE, FRANK A. EWER. 

